Nearly 170 earthquakes within a year in Kon Tum, urgent petition

According to Dr. Nguyen Xuan Anh, Director of the Institute of Geophysics, in the period from 1903 to 2020, in the area of ​​Kon Plong district and the surrounding area, 33 earthquakes of magnitude 2.5 and above were recorded. in which the two strongest earthquakes occurred in 1937 with magnitudes of 3.9 and 3.0 . respectively

However, only from April 2021 until now, statistics show that earthquakes occurring in the area of ​​Kon Plong district and neighboring areas have a regular frequency and a strong trend. Specifically, in 2021 up to now, 169 earthquakes with magnitudes from M >= 2.5 have been recorded. Especially from April 15-18, earthquakes have been recorded continuously in this area with a total of 22 earthquakes with magnitude M = 2.5 to 4.5.

Dr. Xuan Anh said that earthquakes in Kon Plong district have occurred more frequently in recent times and tend to increase in magnitude. Although so far no damage to houses and people has been recorded in the above area, but certainly the seismic vibrations caused by the earthquake have made a certain impact on the lives of people in the area.

In order to minimize the damage caused by earthquakes in the above area, the Institute of Geophysics has just sent a petition to the National Steering Committee for Natural Disaster Prevention and Control to consider allowing the conduct of studies. specializes in earthquake hazards and risks for the area of ​​Kon Plong district, Kon Tum province.

Some specific contents include conducting research and evaluating in detail the structural model and the maximum possible earthquake magnitude of the fault systems in the area of ​​Kon Plong district and surrounding areas. Immediately establish a network of local earthquake observation stations (including 5 stations) in the area of ​​Kon Plong district and surrounding areas. Conduct research on causes of earthquake series occurring in Kon Plong district and surrounding areas.

Besides, conducting risk assessment and developing possible risk response scenarios for Kon Plong district and surrounding areas. Review and evaluate the design of seismic resistance for hydropower projects and important works in Kon Tum province.

According to Dr. Le Huy Minh, Institute of Geophysics, it is likely that the earthquake occurring in Kon Plong is a stimulatory earthquake, which occurs when hydroelectric and irrigation reservoirs accumulate water, putting pressure on the lateral fault system. below.

Assoc. Prof. Dr. Cao Dinh Trieu, an expert in earthquakes, also said that the earthquake in Kon Plong is likely to be a stimulated earthquake because the time of earthquake increase coincides with the time when the Thuong Kon Tum Hydropower Plant is located in the district. Kon Plong operates and generates electricity for unit 1 (March 24, 2021).

In particular, the earthquake area is located on the Rao Quan – A Luoi fault, this is a strong fault zone, running from Laos, through A Luoi (Thua Thien – Hue), extending to Quy Nhon (Binh Dinh). On this fault zone, stimulating earthquakes have been recorded at Tranh 2 hydroelectricity (Quang Nam) and Dak Drinh hydropower (Quang Ngai) when these plants accumulate reservoir water.

In particular, at Song Tranh 2 hydropower plant, earthquakes occurred since 2012, lasting until now, causing many concerns for people and authorities in Bac Tra My and Nam Tra My districts (Quang Nam province). ). At Dak Drinh Hydropower Plant, ignited earthquakes occur in a shorter time, with less intensity and frequency.

According to Assoc. Prof. Dr. Cao Dinh Trieu, in the area where the earthquake occurred in Kon Tum, the maximum natural earthquake is estimated to reach about 5.9 degrees, the maximum earthquake stimulation is lower, maybe less than 5 degrees. Therefore, the magnitude 4.5 earthquake yesterday could be the main trigger (the strongest earthquake in the series of excited earthquakes) of the excited earthquake activity in this area. As a rule, after the main trigger, there will be many other earthquakes of smaller magnitude.

Consecutive earthquakes in Kon Tum are unusual and rare

On the morning of April 19, the National Steering Committee for Natural Disaster Prevention and Control held an emergency meeting with units, ministries, sectors and Kon Tum province on responding to earthquakes that occurred in Kon Long district in the past few days.

From 2021 to now, the number of earthquakes occurring in Kon Plong district is 3.5 times higher than 100 years ago.

Dr. Nguyen Xuan Anh, Director of the Institute of Geophysics, said: “It is forecasted that in the coming time, the Kon Plong area may continue to experience earthquakes, with a magnitude of up to 5-5.5 Richter. The Institute of Geophysics is continuing to monitor for further evaluation.”

The leader of Kon Plong district suggested that the Institute of Geophysics needs to research, survey, evaluate and forecast earthquake changes in the district to have a timely response plan.

Speaking at the conference, Mr. Tran Quang Hoai, Deputy Head of the National Steering Committee for Natural Disaster Prevention and Control, said that the consecutive earthquakes that occurred in Kon Tum in the past few days were unusual. The situation is likely to continue to occur earthquakes in the near future.

Mr. Tran Quang Hoai suggested that the units continue to closely monitor the earthquake situation and provide timely information to avoid causing confusion for people.

Hoai suggested that the Institute of Geophysics continue to closely monitor earthquakes, conduct an overall study, and soon issue warnings and forecasts for the people. At the same time, units must strengthen and coordinate with hydropower and local authorities to provide information quickly, avoiding confusion and affecting people’s lives.

Mr. Hoai suggested that the Kon Tum Provincial People’s Committee assign the task to the Provincial Steering Committee for Natural Disaster Prevention and Control to review and plan responses to possible incidents. Immediately after this meeting, the province needs to send delegations to inspect the areas to closely grasp the situation.

In particular, at present, reservoirs in Kon Tum area are full of water, if an incident occurs, it will be very dangerous. water at this time. Reservoirs and irrigation lakes must regularly check and monitor activities, reduce water storage; at the same time proactively informing people in a timely manner.

According to Nguyen Hoai – Duong Hung